deeper tremolo in silvertone?

[dmartn149]

So in your amp that would be the 1M resistor feeding the 1M intensity pot. Did you try jumpering that resistor or is the amp "back the way it was" circuit wise?

If you get ample satisfaction from the jumper you might try a smaller value resistor (smaller than 1M anyway) rather than a jumper. And don't sweat the action on only the last third of the intensity pot. Pots of different tapers can be found so that can be addressed later.

Thanks Chuck. Yes jumpering that R gives plenty of trem. I'll try different R values there till I'm happy with the max. I'm not worried about the pot taper.

[Chuck H]

I found this on another forum. "1/ Change the R40 680k resistor in serie between the oscillator plate and the trem intensity pot with a jumper.
This should resolve most of you problem." The thread was about a Vox Cambridge trem,..

So in your amp that would be the 1M resistor feeding the 1M intensity pot. Did you try jumpering that resistor or is the amp "back the way it was" circuit wise?

If you get ample satisfaction from the jumper you might try a smaller value resistor (smaller than 1M anyway) rather than a jumper. And don't sweat the action on only the last third of the intensity pot. Pots of different tapers can be found so that can be addressed later.

[dmartn149]

Maybe try replacing the rectifier tube for starters.

Ok, I couldn't keep Chuck in suspense any longer. New rectifier has it back the way it was before I went EXTRA stupid.

[g1]

Maybe try replacing the rectifier tube for starters.

[Chuck H]

...

[dmartn149]

Blows fuses with power tubes removed?

Yes, I'm done working on it for tonight. Not sure what to check when I get back to it. I do have a light bulb limiter.

[g1]

Blows fuses with power tubes removed?

[dmartn149]

My power has been out all day, and I still have a tree laying on my roof. Just prior to the tree falling I did something really embarrassingly stupid. I found this on another forum. "1/ Change the R40 680k resistor in serie between the oscillator plate and the trem intensity pot with a jumper.
This should resolve most of you problem." The thread was about a Vox Cambridge trem, but the REAL problem is that Instead of jumpering the resistor I jumpered the cap. This OBVIOUSLY sent about 300v DC to the grids of the power tubes, burnt the fuse, and apparently damaged something else, because it now JUST blows fuses. Now I just don't have time to look at it.

[g1]

Does your meter have a little bargraph on the display like some of the Fluke's have?

[Enzo]

Maybe a relative reading at the fastest trem speed.

[Chuck H]

I don't think you could measure it with a DMM. The modulation is slow enough that I don't think the meter would average well. Just bounce around. Plus you cannot see the wave form, which was part of the reasoning.

[dmartn149]

I don't have a scope. Could I measure the LFO with an analogue multi meter?

[Enzo]

Stop guessing, find out how the circuit works. Scope it. How much LFO signal is on either side of C14? Then how much at joint between R33 and R34? How much at the Trem FS, and does it vary smoothly?

R21 and R23 should not affect the amount of LFO signal unless the grids are drawing current.

[dmartn149]

I wonder if it could be not enough resistance in my grid stoppers. The schematic shows 330k, mine are 1.7k. When I first built the amp, I left the grid stoppers off. They are not on the layout that I found on line, and they are not on the silvertone 1482 schem. which is otherwise very close to the 1472. When I decided to put them in, I chose resistors closer to the ones used in a 5e3 deluxe. I guess it's easy enough to change them, but not tonight.

[dmartn149]

Are you sure? According to the schematic the grid stops (R23, R25) are also 330k like R21, R22.?. Double check that just to be cautious.

Yeah, I had it wrong. R21 & R22 should be attached to the other end of the grid stops. I had them and the grid stops attached to pin 5. I've moved them now, with no change in the shallow tremolo. Still looking for another error.